Definition: A phytosaurian is a type of dinosaur that lived during the Late Cretaceous Period, approximately 68 to 72 million years ago. They were part of the group known as the "Cretaceous-Paleogene" (K-Pg) period, which saw the rise and decline of the Earth's ecosystems. The phytosaurian was a small, herbivorous dinosaur that lived in a variety of environments, including forests, grasslands, and deserts.